package com.msdp.utils;

import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

import static com.msdp.utils.RedisConstants.INCREMENT_KEY;

@Component
@Slf4j
public class RedisWorker {

    private static final long BEGIN_TIMESTAMP = 1704067200L;

    private final int COUNT_BITS = 32;

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    public long nextId(String keyPrefix){
        //1. 生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long timestamp = now.toEpochSecond(ZoneOffset.UTC) - BEGIN_TIMESTAMP;

        //2. 生成序列号
        //2.1. 获取当前日期，精确到天
        String date = now.format(DateTimeFormatter.ofPattern("yy:MM:dd"));
        //2.2. 自增长
        long increment = stringRedisTemplate.opsForValue().increment(INCREMENT_KEY + keyPrefix + ":" + date);

        //3. 拼接并返回
        return timestamp << COUNT_BITS | increment;
    }
}
